Telegraph system.



J. E. WRIGHT.

TELEGRAPH SYSTEM.

APPUCATION FILED JAN-15.1916.

1,21 9,522. Patented Mar. 20, 1917.

5] 14- we wfoz To all whom it may concern:

JOHN E. WRIGHT, or NEW YORK, n. Y.

TELEGRAPH SYSTEM.

Be it known that 1, JOHN E. VVRIGHT, a

citizen of the United States, residing at New York, in the county andState of New York, have invented certain new and useful Improvements inTelegraph Systems, of. which the following is a full, clear, and ex actdescription. j

In systemsfor the transmission of electrical impulses over a line forthe operation of telegraph instruments, the length of such line, or itscharacter with regard to th'e impedance which it ofi'ers to the readypassage, of impulses of either one or both polarities, often determinesthe amount and character of the work which it is capable of performing.When the inductive efi'ects are of such a nature, for example, that any.one or. a succession of similar impulses sent into the line becomeblocked or perceptibly weak-' ened, some means must, be provided forclearing the line after each impulse or group of impulses in-order topermit of working at practicable or commercial speeds, and many planshave heretofore been practised for this purpose.

The object of the improvement upon which is based the presentapplication for patent, is td improve the character and earrying qualityof the signal impulses of-currentysent over telegraph lines in general,and'ai ulre particularly those in which thein 'ductiue capacity is such'as to tplay an important part in the transmission of impulses andinorder to convey a clear understanding of the 'nature oflthe improvementwe may assume the conditions met'witli in an ordinary case. v Let it beassumed, for example, that we are dealing with a system in which allzimpulses of current sent to line, originate from a suitable source andare directe'd'through the segments of a commutator or sunflowerinstrument, to the relay which sends corresponding impulses over theline. In such cases it is usual to employ a relay designed tooperate asa pole changer, through which all of-such original impulses are sent andwhich operates to transmit over the line from the main battery positiveor negative currents corresponding to the source or direction of thosereceived from the sunflower Patented Mar. 2c, 1917.

Application filed January 15, 1916. Serial No. 72,221.

' segments by the magnet of the pole changer.

It is, for example, a common expedient. to send out from that segmentupon which the contact brush bears when at rest, a negative impulse orcurrent and from the remaining segments, currents from the positive poleof the local battery.

The pole changer habitually used for this purpose is a polarized relaywith an armature or tongue connected to line, and its front and backstops connected with the positive andnegative poles of the source ofline current respectively. In this arrangement when the pole changeris'used, for instance, in connection with a printing telegraphinstrument, the movements of the relay tongue controlled by the impulsesproceeding from the commutator or sunflower segments, respond to thepolarities of the impulses with which the segments maybe charged, as therelay magnet receives them by themovement of the contact brush over suchsegments. If the first segment from which an impulse is received bepositive, the tongue will take-up. a certain position and maintain ituntil a segment with a nega-' tive charge is encountered, the insulationbetween segments with corresponding interruptions of current having noeffect upon the position of the tongue of the pole changer.

' Thus, if the sunflower have eiglit segments which are alternatelycharged positive and negative, the tongue during one revolution of thecontact brush, will make four movements in each direction. On theother'hand, if all the segments are of the same olarity the tongue willnot move at all, and practically only one impulse will be sent to lineduring one rotation of the brush,

thus rendering the line liable to become blocked and offer aniore orless pronounced opposition tothe free passage of impulses, according tocircumstances.

This condition of things I propose to reinedy, by the employinent of apole. changer comprising two independent electromagnets, one normally ina circuit from all the segments of the commutator. or sunflower, and theother in a circuit which is perl'nanently connected with one, thestarting segment,

but adapted by the operation ot the keys or i have shown in theaccompanylng sheet of drawings,

operati combination of signal impulses.

. ture adapted to send to other transmission devices, to be connectedthrough the selective magnets of the translator with such of the other;segments as may be necessary for producing-the desired Each magnet has apivoted circuit controlling armaline animpulse corresponding indirection to the particular selective magnet'that may be operated, andeach adapted on the cessation of any impulse through it, as by thepassage of the rotating contact brush of the sunflower over insulationintermediate to the conducting segments, to connect the line withground,

atc es back stops K are adapted to be connected 665 either to line or tothe positions of the conveniently,

ground according to armatures- E and F, by connecting the armature Ewith the back stop of armature F the" back stop of to ground, and

the back stops-..8 of circuit controllers operated by the'keys ortransmissiondevices of whereby said line is cleared after each inn theinstrument.-

From this arrangement it follows-that 80 pulse Without regard toitsdirection or that of preceding or succeeding impulses.

The details of this invention may perhaps be best explained by adescription of the apparatus and its mode of use which I which is adiagrammatic illustration of such parts of an ordinary composite system,or one'designed for the conjoint use of telephones and 'Morse or similarinstruments, as are necessary for an understanding of the nature andpurpose of my special improvement.

In this diagram assume that A represents the development in a plane ofthe segments of a sunflower disk, in this particular instance eight innumber. A is a local bat-. .tery grounded at one pole and connected atthe other to abrush A" which, we assume, is normally stationary, butadapted, when started, to sweep over the segments in regu-- larsuccession. Normally, the brush rests on segment 1. From this it isstarted by the on of any key of the transmitter, not shown in thisdrawing, ment' first encounters the segment 2, which .is for startingthe sunflowers and 'then passes over segments 3 which send to line theimpulses making up the signal combi-. nations. I

lh'e segment 1 is' permanently connected by wire 4 withfan ordinaryrelay magnet -B,

said wire being grounded. The relay B is provided with armature --E,retracted by a spring *6, and vibrating between stops H and K, and underthe. assumed conditions while the sunflower is at rest, the magnet thearmature E drawn up against the front stop H.

, A second electro-magnet C is also used and connected'by-a wire 5 toground on the onehand and to the'parts or circuits ofthe transmitteroperated according to the.

signals to be sent on the other. This magne is similarly provided withan armature F I and stops H and'K. i The front stops H constitute thepositive and negative terminals of a line battery L, grounded at itsmiddle point M, and both through magnet B and six brush A" and in itsvmovemagnet B normally energized, sends but when the sunflower isstarted, the first i current impulse from segment 2 passes through themagnet 6 and wire 5 through magnet C. By the same. movement brush A thecircuit of rupted, and hence a positive impulse, succeedin'g thenegative impulse, is sent to line by magnet C. I If none of the contactlevers 8 are shifts by the transmitter mechanism, the further movementof. the brush Af'will result in sending six successive impulses ofcurrent corresponding negative impulses to line B, but, in this, and inall cases, it will be observed that the in passing from one segment topasses over insulation S andine current flowingv from the sunthe nextterrup'ts t flower and to ground after each inbrush A reaches thesegment thusconncct selective magnets D ed through one of the withmagnet C, a positive or signal impulse issent to line by the last namedmagnet and then the line is grounded, as above explained.

of the magnet B is inter-- hence denergizes the magnet B or C or both,as the case may be, and this For purposes of the present is I notnecessary to go into a detailed descrip tion of the diagrambeyond thispoint] The latter represents, conyentiorially, an',;ordinarycompositdcircuit which will; be perfectly intelligibleto and is typicalof any other circuit with whloh the invention may be, used, It will beunderstood that in this, as inmany of such systems, the onlycurrentimpulses effective in operating the receiver are those I the linebattery,

from the positive'pole of and that the negative impulses are. for thepurpose of clearing the 15 t, The diagram illustrates anar'ran relythose skillediin t gement 2F h es et e y' s ftsnaatnatthar tweensucceeding impulses,

ordinarily used, and the signals transmitted in the system shown take ona wholly difierent character. They are broken up by the interposition ofa ground connection whenever the sunflower brush passes over theinsulation spaces S between two adjacent segments, at which times, as isobvious, the armature tongues E, F will fall back upon the back stops orcontacts K as the current of the relay magnets is then interrupted. Bythus momentarily connecting the line to ground it will rid itself of theinductive charge caused by the preceding impulse.

From. the above to line during one revolution of the contact brush, theline would be grounded beand would not, therefore, be surcharged by aprolonged wave of current in one direction as would be the case withordinary pole changer transmission.

On a difiicult circuit of high inductive ca; pacity, the five or siximpulses would probably reach the receiving end, under ordinaryconditions, as one impulse, but a gal\"anometer or a milliam'meter T inthe transmission circuit of my system will not swing appreciably fromzero, showing that the line is not being highly charged. The advantageof not overcharging the line is obvious. The path for every impulse iscleared by the connection to ground preceding and following such impulseand the signal rea hes the receiving end through even telephonecomposite circuits, unblurred and well defined.

Another advantageous result secured by the use ot'this compound relaydevice is the virtual cutting of the battery potential in half. Thepositive and negative poles are widely separated and the tendency tosparkmg is greatly reduced, and, in fact, the use of a small condenser Ycompletely eliminates the spark.

Still another advantage derived from the arrangement, and a veryimportant one, is that by its use the noise in the telephone V, whencomposite circuit is used, is measurably .reduced as compared with thatmade by signals from an ordinary pole chan er under like conditions.This to the even charging and discharging of the line, the batterypotential never rising much description and illustration 1t Wlll beobserved that if five 0r- ,v, six impulses 1n the same directlon besent' 'or negative current to relaycomprising two electro-magnets withwhich the.current sending. devices are respectively connected or adaptedto be con:

.nected, and circuit controlling devices actuated by the said twomagnets for transmitting to line currentimpulses of opposite directionand grounding the line after each, transmitted impulse. I 2. In atelegraph system,

rent and a commutator -or sunflower,

a source of ourthe segments of which are adapted to be successivelycharged thereby, in combination with a compound relay comprising twoelectro-nuignets with which the said segments are connected or adaptedto be connected, and circuit controlling means actuated by the saidmagnets for sending impulses of opposite direction to line and forconnecting the said lines to ground after each interruption of currentthrough either magnet, as set forth.

In a telegraph system, a source of ourrcnt and a commutator orsunflower, the segments of" which are adapted to be successively chargedthereby, in combination with two elcctro-magnets andcircuit conuectionsbetween the same and the said segis probably uel above the point reachedby brush contact with one segment. 1

A compound relay of the-general character described is not in itself anew device, but so far as I am aware, ithas never been employed-asIhav'e here shown it, as a pole changer. I have discovered that its useon composite circuits of considerable length has been attended with themost unexpected results, the noise in the telephone, for example,

meats, means for controlling said circuit connections, armatures for themagnets, a. battery, thebpposite poles of which are adapted to beconnected to line by the movements of the armatures, and a connectionbetween the line and ground adapted to be closed whenever the circuitthrough the ma g nets is interrupted.

4. In a composite telegraph system involving the use of transmitting andreceiving teliphone and current impulse operated mechanism, thecombination with the transmission line of a source "of current impulses,a con'ipound relay comprising t-Wo {magnets adapted to be energized bysuch current impulses and to send opposite flowing impulses over theline according towhich' magnet is energized,'and mea'nsopei-ated by suchmagnets toestablish, after each impulse so sent, a connection betweenthe line and. the ground. 1 5. In a telegraph system, the combinationwith a transmitter and means therein for developing current" impulseswhich produce in the line corresponding impulses, ot' a compound relaycomprisirig twonnagnets, one adapted to cmiuectx the positive and theother the negative poles of a battery to line, means for connecting oneor the other magnet in thecircuit of the impulses developed by thetransmitter, according to the nature and purpose of such impulses, andmeans controlled by the magnets for grounding the line after eachtransmitted impulse.

6. In a telegraph system, the combination with transmitting mechanismcomprising a sunflower or commutator, of a compound relay consisting'oftwo neutral electro-magnets, circuit controllers operated thereby,

. magnet with certain one for sending positive and the second negativecurrents to line, permanent connections between one magnet I ments, andmeans for connecting thesecond of the segments when signal impulses areto be transmitted.

In testimony whereof I atlix my signature. i 4 7 JOHN E. WVRIGHT.

and the sunflower seg-

